© 2015

Lyashenko A. O., research worker

Cherkasy experimental station of bioresources NAASU

CORRELATION BETWEEN THE QUALITY INDICATORS OF BULL SEMEN
LONG-TERM STORAGE

Reviewer –Deputy Head of the Department of Livestock, major research associate, PhD in AgricultureY.Sotnichenko

The investigation of the relationship between the physiological, morphological and morphometric characteristics of bulls’ sperm of different breeds of the Bank of genetic resources, depending on the storage term was carried out. We determine the correlation between indicators of sperm of morphology and morphological indexes. We determine the inverse relationshipbetween the content of pathological forms and the number of normal acrosome: the greater number of sperm with normal acrosome, the less number of abnormal cells r= -0,3 (p<0,001). There is a negative correlation between the number of abnormal sperm and HOST (r= -0,54) (p<0,001), between the percentage of damaged acrosome, the number of abnormal cells, the number of pathological and dead cells and the length of the different parts of the sperm (r= -0,2) (p<0,05).

Keywords:cryopreserved sperm, pathological forms, acrosome, morphometry, correlation analysis, long-term storage.

Statement of the problem. Save tribal resources of farm animals is to create gene pool herds with cryopreservation and long-term storage of genetic material in cryobanks [2]. Purpose of cryobanks is the accumulation and long-term storage of genetic resources of all kinds of farm animals, as well as complex organizational and technical measures for the conservation and sustainable use of the available gene pool in Ukraine [1]. Accordingly to the gene pool of breeds conservation programs should be carried out expert evaluation of genetic resources to establish the feasibility of further storage and use in selection process [7].

Analysis of major studies and publications which discuss the problem.Scientific studies of some authors found that motility, survival and fertilizing capacity of deep frozen semen of bulls remain at a high level during prolonged storage. In their study, the authors drew attention to the study of the morphology, physiology and sperm morphometry of bull, but few data to the interdependence between these indicators in terms of long-term storage[5, 8-10].

It is important to get relationship between different measures of morphology and to determine its effect on the physiology and sperm morphometry. It is known that the morphological changes can be applied to all part of the sperm. Most sperm morphological disorders related to the size of certain parts of the sperm and, accordingly, may affect the survival and motility [4, 5, 9]. In the literature there is information about the effect of different term of storage the semen of bullof dairy and beef breeds [3, 4], but not enough data about the relationship between sperm quality characteristics that determines the relevance of our research and there is a scientific and practical interest.

Aimof the research: to establish correlation dependence between qualitative indicators of bull sperm of long-term storage.

Objective: to assess the physiological, morphological and morphometric parameters of bull sperm of dairy and beef breeds of different terms of storage.

Material and methods of the research.In studies we used cryopreserved semen of 160 bulls from 22 breeds of beef, dairy and combined productivity. Term of storage in studied sperm was from 10 to 45 years. We have divided the semen of bulls into three groups: first – the term of storageof 10-20 years, second – 21-30 years and third – 31–45 years. The study of the morphological characteristics of bull sperm was performed in the laboratory of Cherkasy PC SPA «Progres» using microscope Olympus CX-31. Prepared sperm preparations were analyzed at a magnification of 600-1500 times according to GOST 20909.3-75. In exploring the relationship between semen quality parameters was used correlation analysis. The resulting material was treated by research methods of mathematical statistics on algorithms of Plohynskyi N.A. on software package «Statistica - 6.1» in Windows on a PC [6].

Resultsofthe research. According to the research, we conducted a correlation analysis between physiological and morphological parameters of sperm. Direct correlation dependence in experimental sperm samples long-term storage, was set between: straight forward motility (SFM) and survival, motility and sperm count with a straight forward motility (SCSFM), survival and absolute survival rate (ASR), ASR and (hypo-osmotic swelling test) HOST, sperm size and rectilinear velocity, rectilinear velocity and HOST,% of dead sperm and % of abnormal forms (pathological), ASR and normal acrosome, ASRand % of live sperm and others (table 1, 2).

  1. The correlation coefficients between physiological parameters and

morphology sperm of bull (n=170)

Correlation characteristics / Correlation coefficient
survival rate - the number of dead sperm / -0,73±0,02**
survival rate - % pathological forms / -0,45±0,04*
the number of dead sperm – % pathological forms / 0,5±0,04***
SFM - % pathological forms / -0,55±0,04***
ASR – % pathological forms / -0,51±0,04***
% damaged acrosome – sperm head length / -0,29±0,04***
the number of dead sperm - sperm head length / -0,18±0,05***
the number of dead sperm – length tail sperm / -0,12±0,05*
% pathological forms – total sperm length / -0,12±0,05*
% normal acrosome – motility / 0,52±0,04***
% pathological forms – rectilinear velocity / -0,3±0,05*
% pathological forms –HOST / -0,54±0,04***
% pathological forms –% damaged acrosome / 0,3±0,05***
% pathological forms – teratozoospermia index / 0,61±0,02***
% pathological forms – pathology index / 0,97±0,01***
% pathological forms – sperm deformity index / 0,91±0,01***
HOST –% damaged acrosome / -0,44±0,04***
% normal acrosome - % live sperm / 0,51±0,04**
ASR – % damaged acrosome / -0,49±0,04***

Note: *p<0,05; **p<0,01; ***p<0,001

We determined the positive relationship between the number of pathological forms and the percentage of damaged acrosome (r=0,3) (p<0,05) and the probability negative relationship between HOST and the percentage of damaged acrosome (r= -0,44) (p<0.001). In semen the long term of storage turned out such a correlation dependence between ASR and % of pathological forms (r= -0,51) (p<0,001), between the number of pathological sperm and HOST (r= -0,54) (p<0,001), between the number of dead cells and the percentage of damaged acrosome (r=0,51) (p<0,01) and between ASR and of damaged acrosome (r= -0,49) (p<0,001).We established pattern between % of pathological forms and the number of normal acrosome: the greater the number of sperm with normal acrosome, the less abnormal cells r= -0,3 (p<0,001). Inverse correlation dependence in experimental sperm samples the different terms of storage has been established between the percentage of damaged acrosome, % of abnormal forms, the number of dead cells and sperm size (r= -0,12-0,32) (p<0,05) (table 1).

Correlation analysis between sperm morphology parameters and morphological indices was conducted. There are determined probable correlation between % of pathological forms and sperm deformity index r=0,91 (p<0,001), an index of pathology and % of pathological forms r=0,97 (p<0,001), % of pathological forms and teratozoospermia index r=0,61 (p<0,001).As a result of studies, we found that the correlation coefficient between survival and % of pathological forms had a negative value with the average strength r= -0,45 (p<0,05). However, the correlation coefficient between % of pathological forms and rectilinear velocity was negative with medium strength r= -0,3 (p<0,05) (table 1).

The high correlation dependence in the experimental of sperm samples of long-term storage was observed between ASR–SFM r=0,88 (p<0,001), ASR and % of live sperm r=0,85 (p<0,001), SFM and % of live sperm r=0,91 (p<0,001), SFM and SCSFM r=0,71 (p<0,001), HOST and SFM r=0,81 (p<0,001), ASR and HOST r=0,71 (p<0,001). It was established that the coefficient of correlation between the size of the sperm and rectilinear velocity had a positive value of weak strength r=0,15 (p<0,05). However, the correlation coefficient between HOST and rectilinear velocity and total sperm length and HOST was positive with medium strength r=0,21-0,31 (p<0,05) (table 2).

  1. The correlation coefficients between some physiological parameters of bull sperm (n=170)

Correlation characteristics / Correlation coefficient
ASR – SFM / 0,88±0,03***
SFM - dynamic characteristics / 0,37±0,05**
SFM–SCSFM / 0,71±0,02***
ASR– dynamic characteristics / 0,41±0,05*
ASR - % of live sperm / 0,85±0,03***
SFM - % of live sperm / 0,96±0,03***
total sperm length – rectilinear velocity / 0,15±0,05*
rectilinear velocity – HOST / 0,31±0,05*
HOST –SFM / 0,81±0,02***
total sperm length –survival rate / 0,24±0,05*
total sperm length – HOST / 0,21±0,05*
total sperm length –ASR / 0,26±0,05*
ASR– HOST / 0,71±0,03***

Note: *p<0,05; **p<0,01; ***p<0,001

Conclusion. For long-term storage (10–45 years) bull sperm trend to decrease physiological (HOST, ASR,% of live sperm, rectilinear velocity) and morphological parameters (amount of pathological forms, the percentage of normal acrosome) (but within the rules), indicating their interdependence and the importance in assessing the quality of sperm was observed.The research was found that between the majorities physiological parameters was observed mostly probable a positive relationship, and between physiological parameters and sperm morphology mostly negative. Are determined probable a feedback between the content of pathological forms and the number of normal acrosome: the greater the number of sperm with normal acrosome, the less abnormal cells.

BIBLIOGRAPHY:

  1. Буркат В. П. Банк генетичних ресурсів – основа прискореного виведення нових та збереження локальних порід / В. П. Буркат, А. П. Кругляк // Біотехнологічні, селекційні та організаційні методи відтворення, зберігання і використання генофонду тварин : [зб. наук. пр. УААН. Нац. об-ня по плем. справі у тваринництві]. – К., 1997. – С. 173–175.
  2. Зубець М. В. Методологічні аспекти збереження генофонду сільськогосподарських тварин /
    М. В. Зубець, В. П. Буркат, Ю. Ф. Мельник; наук. ред. І. В. Гузєв. – К.: Аграрна наука, 2007. – 120 с.
  3. Ляшенко А. О. Вплив тривалого зберігання кріоконсервованої сперми бугаїв у рідкому азоті на показники якості сперматозоїдів / А. О. Ляшенко // Вісник Полтавської державної аграрної академії. – 2013. – №2. – С. 162–164.
  4. Ляшенко А. О. Морфологічний аналіз сперми бугаїв довготривалого зберігання /
    А. О. Ляшенко // Вісник Полтавської державної аграрної академії. 2014. – №1. – С. 130–133.
  5. Осташко Ф.И. Глубокое замораживание и длительное хранение спермы производителей / Ф.И. Осташко. – К. : Урожай, 1978. – 256 с.
  6. Плохинский Н. А. Руководство по биометрии для зоотехников / Н. А. Плохинский. – М. : Колос, 1969. – 256 с.
  7. Програма збереження локальних та зникаючих порід сільськогосподарських тварин в Україні (згідно з вимогами ФАО). «Збереження генофонду». Інститут розведення і генетики тварин НААН.[Електронний ресурс]. – Чубинське, 2013. – 24 с. – Режим доступу :
  8. Сірацький Й. З. Життєздатність сперматозоїдів від плідників різних молочних порід /
    Й. З. Сірацький, О. В. Бойко, Є. І. Федорович // Тваринництво України, 2010. – №3. – С. 12–16.
  9. Clement F. Sperm morphology and fertility / F.Clement, Y. Ladonnet, M. Magistrini // Animal Reproduction Science. – 2001. – №68. – Р. 362–363.
  10. Johnson W.H. The significance to bull fertility of morphologically abnormal sperm /
    W.H. Johnson // Veterinary Clinics of North America: Food Animal Practice. – 1997. – №13. – Р. 255–270.

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